Molar mass and converting grams to moles

Answer Key - Grade 10 Science Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.

1. 1.

   A glass holds 36.04 g of water. Water's molar mass is 18.02 g/mol. How many moles of water is that, to 0.01 mol, Ari?

   2 mol
2. 2.

   A balloon holds 22.01 g of carbon dioxide (CO₂). Its molar mass is 44.01 g/mol. How many moles is that, to 0.01 mol, Bo?

   0.5 mol
3. 3.

   A spoon holds 14.61 g of table salt (NaCl). Its molar mass is 58.44 g/mol. How many moles is that, to 0.01 mol, Kira?

   0.25 mol
4. 4.

   Table salt is NaCl. Using Na 22.99 and Cl 35.45 g/mol, what is its molar mass, Milo?

   • 28 g/mol
   • 12.46 g/mol
   • 58.44 g/mol
5. 5.

   Water's molar mass is 18.02 g/mol. What does that mean, Noah?

   • One water molecule has a mass of 18.02 g
   • One mole of water has a mass of 18.02 g
   • 18.02 moles of water have a mass of 1 g
6. 6.

   Glucose's molar mass is 180.18 g/mol. What is the mass of 6.022 × 10²³ glucose molecules, Pia?

   • 6.022 × 10²³ g
   • 180.18 g
   • 180.18 g for each molecule
7. 7.

   Which has a mass of 44.01 g, Ren?

   • 1 CO₂ molecule
   • 1 mol of CO₂ molecules
   • 44.01 mol of CO₂ molecules
8. 8.

   On the mole map, which step turns grams of water into moles, Tala?

   • Multiply by 18.02 g/mol
   • Divide by 6.022 × 10²³
   • Divide by 18.02 g/mol
9. 9.

   On the mole map, which step turns moles of salt into grams, Zee?

   • Divide by 58.44 g/mol
   • Multiply by 6.022 × 10²³
   • Multiply by 58.44 g/mol
10. 10.

    Which setup changes 36.04 g of water into moles, Esme?

    • 36.04 g × (1 mol ÷ 18.02 g)
    • 36.04 g × (18.02 g ÷ 1 mol)
    • 36.04 g ÷ (6.022 × 10²³)